Vaporizer



April 25, 1961 P. R. GRUMBACH 2,981,526

VAPORIZER Filed Nov. 2l, 1955 lNVENTOR i Phil/5o Gra/m BY ATTRNEYS United States Patent VAPORIZER Phillip R. Grumhach, 2460 Tiebout Ave., New York, N.Y.

Filed Nov. 21, 1955, Ser. No. 548,122

1 Claim. (Cl. 261-121) This invention relates to vaporizers and to apparatus for effecting the vaporization of a volatile liquid.

Various types of vaporizers have been produced heretofore, but conventional vaporizers have the disadvantage that a vapor-laden stream of gas emitted therefrom contains, at least to some extent, droplets which have not been completely converted to vapor. The occurrence of such droplets, even though minute, frequently is objectionable both from the standpoint of the occurrence of liquid as such and from the standpoint of entraining impurities.

It is a principal object of this invention to provide a vaporizer whereby vapor-laden gas emitted therefrom is essentially free of any entrained droplets.

It is a feature of this invention that apparatus is provided whereby two streams of air or other gas are em ployed, one of which is injected below the surface of a body of liquid so as to pass therethrough as a multiplicity of bubbles and the other of which is emitted substantially above the surface of the liquid so as to become commingled with the other stream in a mixing zone above the liquid s-urface, the commingled mixture then being discharged from the mixing zone of the apparatus. It also is essential in order to attain the aforesaid objectives that the rate of supply of the two streams be controlledso that the stream emitted above the liquid surface will be supplied at approximately four times the rate at which the other stream is injected directly into the body of the liquid below the surface thereof. I have found that when the relative proportions of the two streams of air or other gas have the ratio aforesaid that the occurrence of droplets in the resulting mixture is eliminated substantially completely. On the other hand, if the ratio above mentioned is substantially departed from in either direction the conditions are such that there is an occurrence of unvaporized droplets in the vapor-laden air or gas, on the one hand, or, on the other hand, an excessive departure `from Yefficient Vaporization of the liquid by the air or gas employed.

Further objects, features and advantages of this invention will become apparent in connection with the following description of a typical embodiment of this invention that is shown for purposes of exemplilication and illustration in the accompanying drawing, wherein:

Fig. l is a sectional elevation of a vaporizer embodying this invention; and

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Referring to the embodiment of this invention shown in the accompanying drawings, the vaporizer comprises the container or reservoir which is adapted to hold the body of liquid 11 so that there will be a vapor space 12 above the surface 13 of the liquid in the partial-ly filled reservoir.

The mouth of the liquid reservoir 10 is closed by the cap 14 on which there is secured the vapor discharge line 15 that passes through the cap 14 at about the center thereof so that vapor-laden air or other gas may escape from the vaporizer through the conduit thus provided.

ICC

2 The end of the conduit 15 may be threaded as shown at '16 so as to facilitate the attachment thereto of a closing cap 17 such as that shown in dotted lines for attachment when the device is not in use, or a cap having a restricted orifice providing an outlet orifice of desired size, or a connection to an additional length of conduit.

A connecting member 18 is provided which is shown secured by threaded engagement with the short tube 19 that integrally branches from the discharge conduit 15. The connecting member 18 is adapted to be connected with a source of air or other gas by suitable line, such as line 20 that is indicated in dotted lines in Fig. l.

Two lines lead from theconnecting member 18. The line 21 extends nearly to the bottom of the reservoir 10 so that air or other gas discharged therefrom will be njected into contact with the body of liquid 11 in the form of a multiplicity of bubbles that travel a substantial distance in direct contact with the body of liquid before the gas within the bubbles is released into the vapor space above the surface of the liquid. i

The second line 22 directs air or other gas from the connection 18 so as to be emitted substantially above the surface 13 of the body of liquid. Consequently if air or other gas is supplied simultaneously through the lines 21 and 22 the two streams becomecommingled in the vapor space or mixing zone above the liquid and the resulting vmixture is passed out of the apparatus through the discharge conduit 15.

In the embodiment shown the lines 21 and 22 are the only lines for admitting air or other gas into the vaporizer and the desired control of the relative rate at which the air or other gas is introduced is maintained by using round tubing such that the internal diameter of the line 22 is twice the internal diameter of the line 21. While it is usual practice to use round tubing, the lines 21 and 22 may, if desired, have other cross sectional shape, but where the two lines are connected to a common source of air or other gas under pressure the cross sectional ow capacity of the lines should be such that the cross sectional flow capacity of the line 22 is four times the cross sectional ow capacity of the line 21, or approximately so.

VThe operation, of the device shown in the drawings may be exemplified as follows. Merely for purposes of illustration, the reservoir 10 may have a capacity of about one-half pint and the lines 21 and 22 may have an internal diameter of 1/32 and 1/16" respectively. The conduit 15 may have an internal diameter of about Vs" and provided with a cap having a 1A" bore for the orifice. All that is required to use the device is to introduce liquid to be vaporized into the jar, the amount preferably being approximately that which will fill the jar to about one-half its capacity. The cap 14 is then put in place and the connection 18 is attached to a source of air or other, gas under pressure. If, for example, air is passed into the apparatus one stream will be directed by the line 21 so as to be injected into the body of liquid 11 in the form of a multiplicity of bubbles which rise to the surface and which, because of direct contact with the liquid, take up vapor from the liquid. At the same time air is introduced through the line 22 into the vapor space 12 above the surface of the liquid and when the cross sectional flow capacities of the lines 21 and 22 have at least approximately the ratio relationship above mentioned the two streams become commingled so that any droplets, even of a minute size, which may be thrown into the vapor space above the liquid by the rising and bursting of bubbles at the surface of the liquid become completely converted to vapor, with the result that the commingled streams which are taken from the mixing zone within the vapor space pass out through the discharge conduit 15 so as to carry vaporized liquid only therewith.

The eliicacy of the method and apparatus of this i11- vention has been demonstrated. For example, the vaporizer above described by way of illustrative example was employed for the vaporization of turpentine and in a separate test for the vaporization of alcohol. In each instance a dye was placed in the liquid so that if any liquid carry-over occurred the carry-over would be evidenced by staining. In each case two runs were carried out, one run being conducted when the source of compressed air was maintained at a gauge pressure of 8 lbs. per sq. in. and the other run being conducted utilizing a gauge pressure of 2 lbs. per sq. in. A piece of taut clean white cotton cloth was placed 6" from the orifice of the vaporizer and an observation was made at the end of a lS-minute test period. In no case were any dye marks at all visible. By way of comparison, a conventional vaporizer was used under the same conditions as regards the liquid employed and the air pressure used and in all instances the operation of the conventional vaporizer was such as to result in plainly visible stains on the cloth.

The vaporizer of this invention has many applications. For example, a vaporizer such as that above described is of very great utility in effecting vaporization for such purposes as deodorizing or the extermination of vermin. Such applications are frequently desirable in stores under circumstances such that any liquid droplets are likely to cause injury to furniture, rugs, upholstery, clothing, millinery or the like. It is important, therefore, that the vaporizer be such as not to discharge any entrained droplets into the air and, as the foregoing tests indicate, the vaporizer of my invention may be safely used for such purposes.

In addition to the foregoing, the vaporizer of this invention has applications in other fields using either small units or relatively large units according to the demands imposed by a particular usage. More generally, the method and apparatus may be used for effecting the vaporization of any volatile liquid, the term volatile liquid including liquids or liquid mixtures which comprise a volatile component. In addition to liquids such as alcohol and turpentine, water or other aqueous materials may be vaporized and virtually any other nonaqueous type of volatile liquid. Another application is that of producing a mixture of vapor with oxygen-containing gas so as to provide a combustible mixture for use in an engine or furnace.

While a particular structure has been shown, it is apparent that the structure may be varied widely both as regards capacity and as regards the disposition of the inlet and outlet lines so long as the inlet lines are such that one is adapted to inject the air or other gas below the surface of a body of liquid and the other is adapted to emit the air or other gas substantially above the surface of the body of liquid so that the two streams may be commingled in a mixing zone above the liquid surface in the manner that has been exemplified. While normally both lines are connected to a common source of air or other gas this need not necessarily be the case. Where different sources are employed which may be under different pressures, suitable means are employed whereby the rate of flow may be controlled so that the rate of supply, namely, volume per unit of time, above the liquid surface will be, at least approximately, four times the rate at which the air or other gas is injected below the surface of the liquid in the form of a multiplicity of bubbles which pass therethrough. Whereas in the claim reference is made to streams of air and lines for directing such streams into the apparatus, it is to be understood that the term air is such as to embrace other gases with which it may be desirable to introduce vapor. Moreover, it is not necessary that the air or other gas be identical as between the two streams supplied. For example, ordinary atmospheric air may be introduced by one line whereas the other line may introduce a gas other than air or air to which some additional element or substance has been added such as oxygen.

I claim:

A vaporizer which comprises a reservoir adapted to hold a body of liquid partially filling said reservoir leaving a vapor space above the surface thereof, first air inlet line means of predetermined fixed cross-sectional ow capacity adapted to discharge air therefrom substantially below the surface of the body of liquid for admitting air into direct contact therewith and passage therethrough to the surface of said body of liquid and into said vapor space, second air inlet line means of predetermined fixed cross-sectional fiow capacity adapted to discharge air therefrom substantially above the surface of the body of liquid for admitting air into said vapor space and blending same with air that has escaped from the surface of the liquid into said vapor space after having passed therethrough following discharge from said first air inlet means, and vapor discharge conduit means for discharging vapor laden air from said vapor space, the cross section ow capacity of said second air inlet line means being approximately four times that of said first air inlet line means and the cross sectional flow capacity of said vapor discharge conduit means being substantially greater than the combined cross-sectional flow capacities of said first and second air inlet line means for providing free discharge of said vapor laden air from said vapor space with no substantial pressure build-up under any conditions of use.

References Cited in the file of this patent UNITED STATES PATENTS 43,948 McAvoy Aug. 23, 1864 2,300,774 Cartmell NOV. 3, 1942 2,658,489 Putt NOV. 10, 1953 FOREIGN PATENTS 224,548 Great Britain Apr. 7, 1926 335,305 Germany Mar. 31, 1921 

